package com.huyanqi.core.util;

import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class JsonUtil {
	public static String object2json(Object obj) {  
        StringBuilder json = new StringBuilder();  
        if (obj == null) {  
          json.append("\"\"");  
        } else if (obj instanceof String || obj instanceof Integer || obj instanceof Float  
            || obj instanceof Boolean || obj instanceof Short || obj instanceof Double  
            || obj instanceof Long || obj instanceof BigDecimal || obj instanceof BigInteger  
            || obj instanceof Byte) {  
          json.append("\"").append(string2json(obj.toString())).append("\"");  
        } else if (obj instanceof Object[]) {  
          json.append(array2json((Object[]) obj));  
        } else if (obj instanceof List) {  
          json.append(list2json((List<?>) obj));  
        } else if (obj instanceof Map) {  
          json.append(map2json((Map<?, ?>) obj));  
        } else if (obj instanceof Set) {  
          json.append(set2json((Set<?>) obj));  
        } else {  
          json.append(bean2json(obj));  
        }  
        return json.toString();  
}  
public static String bean2json(Object bean) {  
        StringBuilder json = new StringBuilder();  
        json.append("{");  
        PropertyDescriptor[] props = null;  
        try {  
          props = Introspector.getBeanInfo(bean.getClass(), Object.class).getPropertyDescriptors();  
        } catch (IntrospectionException e) {}  
        if (props != null) {  
          for (int i = 0; i < props.length; i++) {  
            try {  
              String name = object2json(props[i].getName());  
              String value = object2json(props[i].getReadMethod().invoke(bean));  
              json.append(name);  
              json.append(":");  
              json.append(value);  
              json.append(",");  
            } catch (Exception e) {}  
          }  
          json.setCharAt(json.length() - 1, '}');  
        } else {  
          json.append("}");  
        }  
        return json.toString();  
}  
public static String list2json(List<?> list) {  
        StringBuilder json = new StringBuilder();  
        json.append("[");  
        if (list != null && list.size() > 0) {  
          for (Object obj : list) {  
            json.append(object2json(obj));  
            json.append(",");  
          }  
          json.setCharAt(json.length() - 1, ']');  
        } else {  
          json.append("]");  
        }  
        return json.toString();  
}  
public static String array2json(Object[] array) {  
        StringBuilder json = new StringBuilder();  
        json.append("[");  
        if (array != null && array.length > 0) {  
          for (Object obj : array) {  
            json.append(object2json(obj));  
            json.append(",");  
          }  
          json.setCharAt(json.length() - 1, ']');  
        } else {  
          json.append("]");  
        }  
        return json.toString();  
}  
public static String map2json(Map<?, ?> map) {  
        StringBuilder json = new StringBuilder();  
        json.append("{");  
        if (map != null && map.size() > 0) {  
          for (Object key : map.keySet()) {  
            json.append(object2json(key));  
            json.append(":");  
            json.append(object2json(map.get(key)));  
            json.append(",");  
          }  
          json.setCharAt(json.length() - 1, '}');  
        } else {  
          json.append("}");  
        }  
        return json.toString();  
}  
public static String set2json(Set<?> set) {  
        StringBuilder json = new StringBuilder();  
        json.append("[");  
        if (set != null && set.size() > 0) {  
          for (Object obj : set) {  
            json.append(object2json(obj));  
            json.append(",");  
          }  
          json.setCharAt(json.length() - 1, ']');  
        } else {  
          json.append("]");  
        }  
        return json.toString();  
}  
public static String string2json(String s) {  
        if (s == null)  
          return "";  
        StringBuilder sb = new StringBuilder();  
        for (int i = 0; i < s.length(); i++) {  
          char ch = s.charAt(i);  
          switch (ch) {  
          case '"':  
            sb.append("\\\"");  
            break;  
          case '\\':  
            sb.append("\\\\");  
            break;  
          case '\b':  
            sb.append("\\b");  
            break;  
          case '\f':  
            sb.append("\\f");  
            break;  
          case '\n':  
            sb.append("\\n");  
            break;  
          case '\r':  
            sb.append("\\r");  
            break;  
          case '\t':  
            sb.append("\\t");  
            break;  
          case '/':  
            sb.append("\\/");  
            break;  
          default:  
            if (ch >= '\u0000' && ch <= '\u001F') {  
              String ss = Integer.toHexString(ch);  
              sb.append("\\u");  
              for (int k = 0; k < 4 - ss.length(); k++) {  
                sb.append('0');  
              }  
              sb.append(ss.toUpperCase());  
            } else {  
              sb.append(ch);  
            }  
          }  
        }  
        return sb.toString();  
}  
}
